. Catalogue of the mammals of Western Europe (Europe exclusive of Russia) in the collection of the British museum. Mammals. 757 rounded off behind, not obliquely truncate, the occipital condyles barely visible when skull is viewed from above; paroccipital processes slender and inconspicuous, rather closely applied to surface of bullae, their tips descending below lip of foramen magnum, the ridges extending upward from their bases slightly developed, much obscured by the somewhat unusual inflation of petrous portion of squamosal; floor of brain-case nearly smooth, but with slightly indicated me
. Catalogue of the mammals of Western Europe (Europe exclusive of Russia) in the collection of the British museum. Mammals. 757 rounded off behind, not obliquely truncate, the occipital condyles barely visible when skull is viewed from above; paroccipital processes slender and inconspicuous, rather closely applied to surface of bullae, their tips descending below lip of foramen magnum, the ridges extending upward from their bases slightly developed, much obscured by the somewhat unusual inflation of petrous portion of squamosal; floor of brain-case nearly smooth, but with slightly indicated median ridge ; diameter of basioccipital along suture contained about two and one-half times in median length; auditory bullje moderately large, about as in Microtus nrvnlis, though somewhat less evenly inflated, their anterior borders encroaching more deeply into ectopterygoid pits. Inter- orbital region short, abruptly though not deeply constricted, the least width usually greater than that of rostrum, the dorsal surface nearly flat, its outer edges becoming slightly angular in old age though never developing distinct ridges. Zygomata weak, scarcely expanded at middle, rather abruptly though not widely spreading, the two arches parallel through a considerable portion of their extent; deflection of arches slight, the median portion lying about at level of middle of skull; anteorbital foramen relatively smaller than in Microtus arvalis. Rostrum relatively weak, its least depth behind incisors about equal to width at same region ; nasals rather noticeably narrowed behind middle, their posterior border squarely trun- cate at about level of middle of zygo- matic root, the nasal branches of premaxillaries extending a little further backward; incisive foramina scarcely as large as in Mkrotus arvalis, their posterior extremity at level of front of 7h\ their anterior extremity separated from incisors by distance equal to about twice their greatest combined breadth. Palate relatively som
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectmammals, bookyear1912
